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91.
The amount of irreversible injury on renal allograft biopsy predicts function, but little is known about the early evolution of this damage. In a single‐center cohort, we examined the relationship between donor‐, recipient‐, and transplantation‐associated factors and change in a morphometric index of chronic damage (ICD) between protocol biopsies performed at implantation and at 2–3 months. We then investigated whether early delta ICD predicted subsequent biochemical outcomes. We found little evidence to support differences between the study group, who had undergone serial biopsies, and a contemporaneous control group, who had not. In allografts with serial biopsies (n = 162), there was an increase in ICD between implantation (median: 2%, IQR:0–8) and 2–3 months post‐transplant (median 8% IQR:4–15; p < 0.0001). Donation from younger or live donors was independently associated with smaller early post‐transplant increases in ICD. There was no evidence for a difference in delta ICD between donation after cardiac death vs. donation after brain death, nor association with length of cold ischemia. After adjustment for GFR at the time of the second biopsy, delta ICD after three months did not predict allograft function at one yr. These findings suggest that graft damage develops shortly after transplantation and reflects donor factors, but does not predict future biochemical outcomes.  相似文献   
92.
Background The importance of the IGF system in HPT has been previously demonstrated. Additionally, the role of vitamin A in HPT has been reported. Retinoic acid (RA), a derivative of vitamin A, is a ligand for the IGF II receptor (IGF2R). We have evaluated the interactions of RA with the IGF system in a primary parathyroid cell culture model. Materials and Methods Primary cell cultures were prepared from nine patients. Following adhesion, the cells were transferred to serum-free medium and dosed once with growth factors ± RA for 96 hours. Proliferation was assessed by measuring tritiated thymidine incorporation. Results Compared with the control group (100%), both IGF I and II increased DNA synthesis significantly. Retinoic acid significantly reduced the basal DNA synthesis to 82.2% ± 4.2% compared with control (P < 0.05). Retinoic acid ×10−5 M completely abrogated the proliferative actions of IGF II (70.2% ± 9.7%, P < 0.05) but had no significant effect on the IGF I response (P > 0.05). To evaluate the role of IGF2R or IGFBPs in mediating the actions of RA, the IGF II analogs [Leu27]IGF II (10–20-fold reduced IGF I receptor affinity) and des(1–6) IGF II (lower IGFBP binding affinity) were used. The IGF II inhibitory effect of RA was enhanced in the presence of analogs [Leu27]IGF II (P = 0.052) but not with des(1–6)IGF II (P > 0.05), compared with wild-type IGF II. Conclusions These data implicate a novel antiproliferative role for RA in enhancing the pericellular clearance of IGF II via the IGF2R preventing ligand activation of the IGF I receptor. This may have broader implications for RA effects in other tumors.  相似文献   
93.
Testicular metastasis as the first manifestation of colon carcinoma   总被引:1,自引:0,他引:1  
Metastatic carcinoma to the testes is uncommon, and it is most often found incidentally at autopsy or after orchiectomy for prostatic carcinoma. One of the rarest causes of testicular tumor is metastasis from another primary site. It is even more unusual when the metastasis to the testicle is the first manifestation of the tumor. We report a case of asymptomatic colon carcinoma presenting as metastases to the testis and epididymis, which was diagnosed after biopsy of testicular nodules. Although nonlymphomatous cancer presenting as an intrascrotal mass is extremely rare, seldom detected clinically and almost never the first sign of disease, it should be considered a possibility, even in the young adult who presents with a mass involving the testicle or epididymis.  相似文献   
94.
We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse.  相似文献   
95.
The retroperitoneal approach has been recently advocated as an alternate approach to abdominal aortic surgery rather than the traditional transperitoneal approach. A comparative analysis of these two approaches was undertaken to clarify the differences. From June 1984 through June 1986, 172 patients underwent elective infrarenal abdominal aortic surgery on the Vascular Surgery Service at Eastern Virginia Medical School. One hundred nineteen were operated through a transperitoneal approach, and 53 through a retroperitoneal approach. The two groups were similar relative to age, sex, indications, risk factors and operations performed. The groups were then analyzed relative to operating time, blood transfusion, fluid replacement, ileus, morbidity, length of hospital stay, American Society of Anesthesiologists classification, and mortality. Significant differences were found: retroperitoneal patients had shorter operating time, shorter ileus, fewer cardiac complications, and shorter hospitalization than transperitoneal patients. This retrospective evaluation supports the conclusion that the retroperitoneal approach to abdominal aortic surgery is safe and beneficial in most patients. The retroperitoneal approach should therefore be given consideration in routine aortic surgery.  相似文献   
96.
It has been shown that the thymus can be regenerated in intact old rats by implanting s.c. a stable analogue of LHRH. Old male rats were given s.c. implants of osmotic pumps containing a solution in citrate buffer of the analogue which was given at a rate of 1 microgram/h for 28 days. Some animals were given pumps containing buffer alone, and another group of rats was orchidectomized. The animals were killed after 28 days and the tissues weighed and taken for histology. Serum testosterone was measured by radioimmunoassay. Sham-treated rats had small fatty thymuses, which were poorly organized with a very narrow band of cortex. Animals treated with the analogue of LHRH and those which had been orchidectomized had relatively large thymuses which were multi-lobed in drug-treated rats, and atrophied accessory sex organs. The testes were grossly atrophied in analogue-treated rats. Histologically, the thymus looked healthy, having a wide, thymocyte-filled cortex and a clearly defined corticomedullary junction. Serum testosterone concentrations were similar in orchidectomized and analogue-treated rats. It is concluded that it is possible to regenerate the thymus in old rats treated with an analogue of LHRH, but the effect is accompanied by chemical castration. It is also clear that the old pituitary gland is susceptible to the desensitizing action of an LHRH analogue.  相似文献   
97.
Physician practices in the prevention of venous thromboembolism   总被引:1,自引:0,他引:1  
OBJECTIVE: To determine the rate of use of prophylaxis for venous thromboembolism in high-risk hospital patients. DESIGN: A retrospective medical record review. SETTING: A community-wide study in 16 short-stay hospitals in central Massachusetts. PATIENTS: A total of 2017 patients with multiple risk factors for venous thromboembolism. MEASUREMENTS AND MAIN RESULTS: On the basis of age, length of hospitalization, and the presence of at least one additional major risk factor, 17% of 151,349 discharges (25,410 patients) were identified as being at high risk for venous thromboembolism. Eight percent of these discharges were randomly selected for medical record review. Prophylaxis for venous thromboembolism was received by 32% of these high-risk patients. Prophylaxis use among the 16 study hospitals varied widely, ranging from 9% to 56%, and was higher in teaching hospitals than in nonteaching hospitals (44% compared with 19%; P less than 0.001). One or more of the following methods of prophylaxis was used: low-dose heparin (78%), intermittent calf compression (13%), warfarin (12%), and inferior vena caval filter (3%). Use of prophylaxis increased with the number of risk factors identified (P less than 0.001). CONCLUSION: Prophylaxis for venous thromboemobolism is underused, particularly in nonteaching hospitals.  相似文献   
98.
99.
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems.  相似文献   
100.
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